1. Field of the Invention
The present invention pertains to a device for use by a disk jockey, wherein electromagnets create the variable slippage tension or friction effect between the user manipulated vinyl-like surface (simulating a vinyl record) and the platter, which may be rotatable or fixed.
2. Description of the Prior Art
Disk jockeys (DJs) traditionally entertain their audiences by manipulating the speed and direction of a vinyl record used on phonographic turntables to produce various effects including the well known “scratch effect”. The turntable has been replaced by CD players that have jog wheels in the form of a turntable like platters that can be turned by the DJ to produce the scratch effect and simulate other characteristics of manipulating a vinyl record on a traditional phonographic turntable.
An improvement on this is to rotate the platter by means of a motor and to provide a separate vinyl-like surface that the user manipulates. Between the motorized platter and vinyl-like surface is a slip disc made of plastic or felt. As the DJ moves the vinyl record-like surface, the slip disc allows the user to move the record independently of the rotating platter. U.S. Pat. No. 6,985,418 entitled “Optical Disk Reproducing Apparatus” to Hori teaches a device that includes an optical disc player, a user manipulated surface and driven rotating surface where there is some type of encoding mechanism to detect the speed and direction of both the user surface and the rotating surface.
The next evolution beyond the moving platter CD player for DJs is the moving platter computer interface control surface. Many DJs desire to use a phonographic turntable-like control surface to manipulate music on their computer. U.S. Pat. No. 6,541,690 entitled “Scratch Effect Controller” to Segers, for example, teaches such a device that manipulates an audio stream on a personal computer using a device that includes a rotating platter, a user manipulated surface (encoder disc), and a slip disc.
One problem with this combination of motorized platter and vinyl-like surface is cost. It is desirable to have a CD player with some of the characteristics of the vinyl-like surface and motorized platter without the platter being motorized.
Another problem not addressed by any of the prior art is the fact that each user may have a different preference as to the feel of the slippage between the vinyl-like record and the rotating platter. On a traditional phonographic turntable, the user may choose from different various slip discs made from a variety of different materials. This does not always produce the most desirable results. All of the above motorized and non-motorized CD players and DJ control surfaces have a similar limitation.